In recent years, the overwhelming amount of observational data supporting the \emph{late-time accelerated expansion of the Universe} has thrusted cosmology in particular and gravitation in general to the forefront of scientific research. In fact, the problem of the origin of the so called \emph{dark energy}, stands as one of the most tantalizing scientific issues of today's theoretical investigations, both in the field of fundamental physics and in that of astrophysics. In this context, note must be given to the appearance of modifications of Einstein's General Relativity, especially designed...